Subnet Calculator

Network Address:
First Usable Host:
Last Usable Host:
Usable Hosts:

You can use this subnet calculator to verify your answers to the questions on our subnetting practice and basic subnetting practice pages.

You can use it to calculate all the subnet information you need. It’s fast, it’s easy, it allows you to cut and paste and it accepts both CIDR (/24) and netmask notation ( You may also want to learn how to subnet or check out the more advanced VLSM calculator which allows you to plan a whole network out.

Download our Subnet Cheat Sheet for all the essential information you need to quickly perform subnet calculations in your head.

If you want to learn more about networking and get the Cisco CCNA certification, we highly recommend the Cisco CCNA Gold Bootcamp as your CCNA training course. The CCNA is by far the most in-demand networking certification by employers, and the Gold Bootcamp is the highest rated Cisco course online. It has an average rating of 4.8 from over 30,000 public reviews:

Cisco CCNA Gold Bootcamp training course